The Italy striker Antonio Cassano is to undergo minor heart surgery after being taken ill on the club's flight home from their 3-2 win over Roma.

Cassano has been receiving treatment since Saturday when he suffered what the club described as a brain problem. He was reportedly joking with team-mates on the plane before suddenly developing difficulties with his vision, speech and movement.

Milan said in a statement that Cassano will undergo the heart procedure some time in the next few days after being diagnosed with a cardiac anomaly, which impaired blood flow to his brain.

His recovery time will be better determined after the surgery, but the Milan vice-president, Adriano Galliani, said: "Presumably within four, five or six months Cassano should be cleared to play. He has a minor heart problem that caused this minor discomfort and over the next few days he will undergo surgery to close the opening."

Zlatan Ibrahimovic, Galliani, the coach Massimiliano Allegri and the Italian federation president, Giancarlo Abete, all visited Cassano at the Policlinico di Milano, where he was being treated on Wednesday.

"Antonio is in a good condition, the lad is fine but I'm not a doctor," Galliani said. "I was very, very worried. His career is not at risk. The doctors say he will need a few months, not too many, although I don't want to say too much at this stage, maybe in four, five or six months he will be in condition to play. He has told me that he's upset because he had been playing well."

Abete said: "The most important thing is his complete and quick recovery, and whenever it will be, it will be. We will stay in constant contact with the club and will do everything in his interest. His health comes first, the rest afterwards."

Cassano's condition leaves Italy without their two starting forwards as they prepare for next year's European Championship finals, with Giuseppe Rossi out following knee surgery.

Diego Maradona wrote a letter of support that was published in Corriere dello Sport on Wednesday. "I know about the thoughts, worries and torments that are going through your mind. I know that feeling of confusion and, why not, even solitude, that makes everything suddenly look black," Maradona wrote.

"I know well, and that's why I feel close to you and Rino Gattuso, who is also experiencing a sad period."

Cassano's hospitalisation came less than a week after the Milan midfielder Gennaro Gattuso announced the extent of a nerve problem affecting his left eye, which could keep him out for months, or the rest of the season.